Japanese Encephalitis Vaccine
Conditions
Brief summary
The main objective of this study is to evaluate the persistence of Japanese encephalitis antibodies in participants at the age of 6, after they have followed different Japanese encephalitis vaccination schedules. Furthermore, the study will assess the immunogenicity and antibody persistence of primary immunization across different Japanese encephalitis vaccination schedules, as well as the immunogenicity following booster immunizations within these schedules. The safety of each vaccine dose will also be evaluated.
Detailed description
This is a randomized, controlled, open-label, non-inferiority study. Healthy children aged 8 months will be invited to participate and randomly allocated to six groups (Group 1 to Group 6) in a 1:1:1:1:1:1 ratio. They will be administered the inactivated Japanese encephalitis vaccine (JEV-I) and/or the live attenuated Japanese encephalitis vaccine (JEV-L) based on the six schedules delineated in the protocol. The primary immunization will be administered to participants at 8 months of age, and a booster dose will be given at 24 months of age. Additionally, participants in Groups 1, 2, and 5 will receive an additional booster dose at the age of 6. Blood samples (3 mL) will be collected from participants at 8 months, 24 months, and 6 years of age. Samples will be taken before vaccination and 30 days after it for detecting Japanese encephalitis neutralizing antibodies. The titers of these antibodies will be assayed via the 50% plaque reduction neutralization test. Those in groups 3, 4, and 6 who've completed all immunization procedures by 24 months old will have a blood sample taken at 6 years old.
Interventions
BIOLOGICALJapanese Encephalitis Vaccine (Vero Cell), Inactivated
0.5ml for each dose, manufactured by Liaoning Chengda Biotechnology Co., Ltd., administered in the deltoid area of lateral arm by intramuscular injection.
BIOLOGICALJapanese Encephalitis Vaccine, Live
0.5ml for each dose, manufactured by Chengdu Institute of Biological Products Co., Ltd., administered subcutaneously in the lower part of the deltoid area of lateral arm.
Sponsors
Liaoning Chengda Biotechnology CO., LTD
Zhejiang Provincial Center for Disease Control and Prevention
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
8 Months to 8 Months
Healthy volunteers
Yes
Inclusion criteria
* Healthy children aged 8 months who are permanent residents of the study area. * Legal guardians can understand the requirements and processes of the study, provide written informed consent, and comply with all procedures as required by the clinical research protocol. * Able to receive the full course of Japanese encephalitis vaccinations according to the immunization strategy in the research protocol, including receiving the primary immunization at 8 months of age and the booster immunizations at 24 months of age and 6 years of age.
Exclusion criteria
* Unable to finish the full course of primary and booster immunizations at the study area, and unable to fulfill the follow-up visits prescribed in the protocol. * Non-compliance with the vaccination strategy for each group, as stated in the protocol, regarding Japanese encephalitis vaccines with proper doses and varieties. * Allergic to any component of the study vaccine or having a history of allergic reactions to any vaccines. * Having a history of symptoms or signs of neurological diseases or other contraindications for Japanese encephalitis vaccine vaccination. * Having used immunosuppressants or blood products following birth. * Receiving other vaccines simultaneously while receiving the Japanese encephalitis vaccine of this project. * Any conditions that may interfere with the evaluation of the study, as deemed by the researcher.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percentage of Participants Testing Seropositive for Japanese Encephalitis Neutralizing Antibodies | 4 years after the booster vaccination at 24 months of age | The persistence of immunity following various Japanese encephalitis (JE) vaccination schedules is evaluated based on the proportion of participants exhibiting seropositivity for JE neutralizing antibodies at 6 years of age. Seropositivity is defined as a JE neutralizing antibody titer of at least 1:10, as ascertained by the 50% plaque reduction neutralization test. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Seroconversion Rates of Japanese Encephalitis Neutralizing Antibodies after Primary vaccination | 30 days post-primary immunization | The seroconversion rate is defined as the percentage of participants with a change in Japanese Encephalitis neutralizing antibody titer from \<1:10 at baseline (pre-vaccination) to a titer of ≥1:10 30 days post-vaccination, or a 4-fold or greater rise from the baseline, as measured by the 50% plaque reduction neutralization test |
| Geometric Mean Titer of Japanese Encephalitis Neutralizing Antibodies before and after Primary Immunization | pre-primary immunization (Day 0) and 30 days post-primary immunization | — |
| Percentage of Participants Testing Seropositive for Japanese Encephalitis Neutralizing Antibodies before and after Primary Immunization | pre-primary immunization (Day 0) and 30 days post-primary immunization | Seropositivity is defined as a Japanese Encephalitis neutralizing antibody titer of at least 1:10, as ascertained by the 50% plaque reduction neutralization test. |
| Seroconversion Rates of Japanese Encephalitis Neutralizing Antibodies after Booster vaccination | 30 days post-booster immunization | The seroconversion rate is defined as the percentage of participants with a change in Japanese Encephalitis neutralizing antibody titer from \<1:10 at baseline (pre-vaccination) to a titer of ≥1:10 30 days post-vaccination, or a 4-fold or greater rise from the baseline, as measured by the 50% plaque reduction neutralization test |
| Geometric Mean Titer of Japanese Encephalitis Neutralizing Antibodies before and after booster Immunization | pre-booster immunization (Day 0) and 30 days post-booster immunization | — |
| Percentage of Participants Testing Seropositive for Japanese Encephalitis Neutralizing Antibodies before and after booster Immunization | pre-booster immunization (Day 0) and 30 days post-booster immunization | Seropositivity is defined as a Japanese Encephalitis neutralizing antibody titer of at least 1:10, as ascertained by the 50% plaque reduction neutralization test. |
| Incidence of any Local and Systemic Adverse Events Within 30 Days of Each Vaccination | within 30 days of each vaccination | Adverse events will be collected through a combination of proactive visits by researchers and participant reports |
Countries
China
Contacts
STUDY_DIRECTORHuanyu Wang
Liaoning Chengda Biotechnology CO., LTD
Outcome results
None listed